The Mechanics and Rhetoric of Conversation : Page 35
However, I would caution that when in doubt as to the policy with regard to a particular word or expression, it is best to stay on the side of the dictionary. This is especially true for professional people — priests, doctors, teachers. In language as in morals, while the larger part of mankind shrewdly tries to pull its leaders down to its own level, a
smaller and better part hopes and expects that those placed higher will maintain what is thought to be the true standard. If there are such in any locality, who know and secretly prefer the dictionary usage, it is well not to disappoint them, "to let them down," as it were. However, when the dictionary allows a choice, one should unhesitatingly use the second choice if it is more adapted to one's inclination or audience.